Modern data processing systems, such as general purpose computer systems, allow the users of such systems to create composite data files which include a variety of different types of data formats. The information often has a composite nature, and the modern computer system allows the integration of these components into a composite data file. For example, a typical document contains text, generated from a text editing program or a word processing program such as Microsoft Word, and may also contain images, generated from an image processing program such as Adobe's PhotoShop program. The document can also contain an embedded document, thus creating an arbitrarily deep hierarchy of data storage. Other examples include a drawing or CAD document containing text objects, a video project containing multiple audio and video clips, an audio/video clip containing information about persons such as the copyright holders, an archive document containing multiple documents, which themselves may be composite documents and multiple directories, which contain multiple documents. In addition, there are numerous other types of files and formats that are capable of being created or modified, edited, and otherwise used for a typical data processing system. The arbitrarily deep level of information storage within a document can present a challenge to a typical user who is seeking to find particular information.
Modern data processing systems often include a file management system which allows a user to place files in various directories or subdirectories (e.g. folders) and allows a user to give the file a name. Further, these file management systems often allow a user to find a file by searching for the file's name, or the date of creation, or the date of modification, or the type of file. An example of such a file management system is the Finder program which operates on Macintosh computers from Apple Computer, Inc. of Cupertino, Calif. Another example of a file management system program is the Windows Explorer program which operates on the Windows operating system from Microsoft Corporation of Redmond, Wash. Both the Finder program and the Windows Explorer program include a find command which allows a user to search for files by various criteria including a file name or a date of creation or a date of modification or the type of file, and even the file content. However, this search capability searches through information only at the top level and for a particular type. Thus, for example, the searchable data for a Microsoft Word file is the text contained in the document, or other related data such as the file name, the type of file, the date of creation, the date of last modification, the size of the file and certain other parameters which may be maintained for the file by the file management system. The searchable data do not include information about embedded files such as a drawing or a image file in the Microsoft Word file.
Further, certain presently existing application programs allow a user to maintain data about a particular file. This data about a particular file may be considered metadata because it is data about other data. This metadata for a particular file may include information about the author of a file, a summary of the document, and various other types of information. A program such as Microsoft Word may automatically create some of this data when a user creates a file and the user may add additional data or edit the data by selecting the “property sheet” from a menu selection in Microsoft Word. The property sheets in Microsoft Word allow a user to create metadata for a particular file or document. However, in existing systems, a user is not able to search for information deep within the document using one search request from the user. Furthermore, existing systems can perform one search for data files, but this search does not also include searching through metadata for those files.